In the concept of computer working, hardware is a real worker of the computer, and software refers to an operating system kernel, operating system (OS) and application program. The operating system kernel controls the hardware to work correctly, for example, enables a CPU to receive instructions and a hard disk to be accessed. The operating system provides a program developer with the environment for developing application programs on the operating system kernel providing drivers. The application program enables an easier communication between the operating system kernel and the user by providing, for example, text instruction mode, graphic mode, etc.
A test environment for many application programs is integrated with and provided on a server; for example, various operating systems are built on an operating system kernel to test different application environments. For example, there is a main operating system built on a GNU (GNU's not Unix) Linux kernel, and a sub operating system is started in the main operating system; then, a first application program runs in the main operating system and a second application program runs in the sub operating system. Because the main operating system and the sub operating system each are an independent operating system for the GNU Linux kernel, it is necessary to build a virtual machine on the main operating system by using a virtual machine technology to integrate the sub operating system into the main operating system, so that the first application program running in the main operating system and the second application program running in the sub operating system can display their respective results on a same screen even under different operating environments.
However, although a virtual machine can be used to integrate two different operating systems on an operating system kernel, such a method requires a higher hardware specification such as, for example, more memory spaces; also, the CPU loading will increase when the virtual machine is started to execute respective application programs of different operating systems.